Flash games use Flash technology for browser games with a wide variety of game genres that the oldies probably played, some calling it the golden age of the internet.
Ah, yes, you can probably ask grandpa (not your actual gramps, probably your uncle) about the browser games he played in the old days, like Territory War, a classic war-shooter game to test your strategy and grit against a computer or your buddy beside you. That's right, your buddy beside you, not online! Another Flash game classic grandpa (again, probably not your actual gramps) played was Fancy Pants Adventure, a classic platforming adventure game where you play as a doodle guy with some awesome, fantastic, fancy pants. Such a venture is timeless, playable now, and just as fun as back in the day. There have been many copies of Interactive Buddy, the OG rage-releasing game where you beat up this poor fella that probably hasn't done anything to you. Beat him up and gain money to buy things to beat him up some more. These are just some of the Flash games of the old days, but your grandpa (not actually) can probably tell you about all the Flash games he used to play and more!